Abstract
Objective To characterize the relationship between the duration of antibiotic administration
during the first week of life and subsequent growth velocity during hospitalization.
Study Design This was a retrospective study comparing the inhospital growth of infants born between
30 and 326/7 weeks' gestational age (GA) admitted to the Montefiore Weiler and Wakefield neonatal
intensive care units between January 2009 and December 2015. Antibiotic duration during
the first week of life was classified as no antibiotics, <5 days of antibiotics, or
≥5 days of antibiotics. Differences between discharge and birth weight Z-scores were
compared between the three groups using analysis of variance.
Results Of the infants, 87% received antibiotics during the first week of life, with 16%
of infants completing ≥5 days. Compared with infants receiving ≤ 5 days of antibiotics,
infants treated with ≥5 days had a lower GA, lower Apgar scores, more invasive respiratory
support, longer duration of total parenteral nutrition, delayed initiation of enteral
feeding, and a higher weight Z-score on admission and discharge (p < 0.05). However, there was no distinction in growth between the three groups assessed
by the difference between admission and discharge weight Z-scores (p = 0.64), growth velocity (gram/kilogram/day) (p = 0.104), or an exponential growth velocity outcome (p = 0.423).
Conclusion Early antibiotic exposure was not associated with increased growth velocity between
birth and discharge. Our study was limited by its retrospective nature and lack of
follow-up data postdischarge.
Keywords
growth - antibiotics - prematurity - metabolic syndrome
